Triphenylmethane dye.



UNITED STATES PATENT OFFICE.

ARTHUR HAUSDORFER, F ELBERFELD, AND CAR-L HEIDENREIGH, OELEVERKUSEN,

GERMANY, ASSIGNORS T0 FARBENFABRIKEN VORM. FBIEDR. BAYER & ELBERFELD,GERMANY, A CORPORATION OF GERMANY.

TRIPHENYLMETHANE DYE.

No Drawing.

Patented Mar. 26, 1912.

To all whom it may concern:

Be it known that we, ARTHUR HAUS- 1 poems and CARL HEIDENREIGH, doctorsof philosophy, chemists, citizgens of the German Empire, residing,respectively, at Elberfeld and Leverkusen, Germany, have invented newand useful Improvements in Triphenylmethane Dye, of which the followingis a specification.

In United States Patent No. 980251 we have described generallydyestufi's obtainable by reacting with the diazo compounds of thetriphenylmethane leuco compounds derived from 'an aminobenzaldehyde andan aromatic oxy-carboxylic acid upon an.azo dyestufl' component andoxidizing the leuco compounds. In the present' application we wish tospecifically describe and claim the product made from2.6-dich1oro-5-aminobenzaldehyde-ortho-cresotinic' acid and 1-sulfophenyl-3-methyl-5-pyrazolone having most probably the formula:

.of a solution of 10.5 parts of sodium nitrite in 200 parts ofconcentrated sulfuric acid. To produce the coloring matter from thediazoleuco compound after 1 to 2 hours a solution of 10.5 parts ofsodium nitrite .in .200 parts of concentrated sulfuric acid is added.

The mixture is then warmed to 3540 C. during 15-20 hours until theoxidation is complete. The redsolution ispoured on ice, the precipitateis filtered off, washed with water and then with a l per cent. sulfuricacid. The diazo compound is stirred up with 600 parts of ice water andadded to a solution of 40.25 parts ofl-sulfophenyl-3-methyl-5-pyrazolone in 40 parts of sodium carbonate and400 parts of water. When the copulation is complete the mixture isheated to 60 C., the dye is preci itated with common salt, filtered Thenew dye is a red powder easily soluble in water with a yellowcoloration. It dyes wool from acid baths red-brown shades which on beingtreated with bichromate change into a green fast to fulling, potting andlight.

We claim v The herein-described new dyestufi' having most probably theformula:

cnnsoai coon I on N/- con v ARTHUR imosoi'mrnnf 1.235;

CARL HEIDENREICH. [1,. 3.] Witnesses:

A. NUFER,

IIeLnN Nurse.

